Martin boehler



UNITED STATES PATENT OFFICE.

MARTIN BOEHLER, OF FRANKFORT-ON-THE-MAIN, GERMANY, ASSIGNOR TO LEOPOLD CASSELLA & 00., OF SAME PLACE.

PROCESS OF DYEING DARK BLUE.

SPECIFICATION forming part of Letters Patent No. 625,717, dated. May 23, 1899;

Application filed December 10,1898. Serial No. 698,882. (No specimens.)

To all whom it may concern:

Be it known that LMARTIN BOEHLER,a citi zen of Prussia,and a resident of Frankfort-onthe-Main, Hesse-Nassau, Germany, have invented certain new and useful Improvements in the Production of Blue Shades on Cotton, of which the following is a specification.

I have found that dyeings produced with the dyestufis commercially named immedial blacks, which are described in the United States Letters Patent N 0. 610,541, dated September 13, 1898, and derived from oxydinitrodiphenylamin, sulfid of sodium, and sul- Example: Twenty kilos cotton are dyed at a temperature of 80 centigrade in a bath of four hundred literswatercontainingonekiloimme dial black V. extra, eight-tenths kilo sodium sulfid, and twelve kilos common salt. The

cotton is allowed to remain in the bath during about one hour, then lifted and rinsed, then entered into a second bath, to which some ammonia-two liters of a solution containing ten per cent. of hydrogen dioxid -has been added. The reaction is terminated after treating the cotton for about one-half hour in this bath at a temperature of about 80 centigrade.

Having thus described my invention and in what manner the same can be performed, What I claim as new, and desire to secure by Letters Patent, is-

The process of producing dark blue shades on the cotton fiber by treating with hydrogen dioxid the dyeings done with the dyestuifs derived by heating oxydinitrodiphenylamin with sulfid of sodium and sulfur,- substantially as described.

Signed at Frankfort-on-the-Main, in the Province of I-IesseNassau and Empire of Germany, this 25th day of October, A. D. 1898.

MARTIN BOEHLER.

Witnesses:

JEAN GRUND, FRANK H. MASON. 

